Problem printing from SD card (no replies)

Hi,

I encountered a problem with my SD card printing. I used to be able to print from SD card but recently I have been encountering some problem even mounting and unmounting my SD card.

I am using Repetier-Host Mac 0.56. Running Marline firmware on a Gen 6 board.

This is what I get when I try to mount my SD card:


PM 11:15:20: Attempting to connect to printer
PM 11:15:20: Connection opened
< PM 11:15:25: start
< PM 11:15:25: echo: External Reset
< PM 11:15:25: Marlin 1.0.0
< PM 11:15:25: echo: Last Updated: Sep 30 2013 16:00:13 | Author: (none, default config)
< PM 11:15:25: Compiled: Sep 30 2013
< PM 11:15:25: echo: Free Memory: 588 PlannerBufferBytes: 1232
< PM 11:15:25: FIRMWARE_NAME:Marlin V1; Sprinter/grbl mashup for gen6 FIRMWARE_URL:[www.mendel-parts.com] PROTOCOL_VERSION:1.0 MACHINE_TYPE:Mendel EXTRUDER_COUNT:1
< PM 11:15:28: Begin file list
< PM 11:15:28: echo:Cannot open subdir
< PM 11:15:28: 501
< PM 11:15:28: End file list

Sometime, Instead of the "echo:Cannot open subdir", I get:

< PM 11:20:01: Begin file list
< PM 11:20:01: Error:0
< PM 11:20:01: : Extruder switched off. MAXTEMP triggered !
< PM 11:20:01: Error:Printer stopped due to errors. Fix the error and use M999 to restart. (Temperature is reset. Set it after restarting)
< PM 11:20:01: ~cho:Cannot open subdir

Anyone able to pinpoint where is the error? Is it due to the SD card? I tried to reformat my SD card before and I still get the same thing.

Thank you!

Wilson